Fix potential NPE
ref #7887 Terms cannot be dropped above or below TermVocabulary any more
ref #6805 i18n
ref #7887 i18n
ref #7887 Avoid moving a term onto itself or its children
Rename utility method
ref #7887 Fix possible NPE when dropping on same term
ref #6806 Add isDirty() to IE4SavablePart + extract dirty check to util
ref #7887 Use DTOs in term editor
ref #6925 Inject context into operations to allow sync/async execution
fix #6922 Migrate Term Editor